Synergistic and Trade‐Off Effects of Plant Communities on Slope Runoff and Sediment Yield

Plant community functional structure plays an important role in regulating slope runoff and sediment yield on the Loess Plateau. Based on runoff plot monitoring and vegetation surveys in the Yangjuangou catchment, we used partial least squares regression (PLSR) and variable importance in projection (VIP) analysis to assess the effects of community functional structure on runoff coefficient and soil loss per unit rainfall. Runoff and sediment yield were affected by a largely similar set of community functional structure indices, although their relative contributions differed between the two processes. Among these indices, the community weighted mean of total root length was the most important for both runoff and sediment yield. Functional diversity indices also contributed more to sediment yield than to runoff. These results suggest that runoff and sediment yield are governed by similar components of community functional structure, whereas sediment yield is more strongly associated with functional diversity. This study provides a basis for vegetation restoration, species selection, and community assembly aimed at soil and water conservation on the Loess Plateau.